1. Field of the Invention
This invention relates to apparatus for inserting and ejecting an electronic enclosure within a cabinet, and, more particularly, to providing forces with such apparatus for the engagement and disengagement of electrical terminals despite variations in the width of the electronic enclosure.
2. Summary of the Background Art
A number of multiple computer installations, such as installations in which a number of servers are connected with one another and with communications lines, individual computer systems are installed within individual electronic enclosures mounted in individual positions, or “slots,” within a cabinet. Such computer systems are configured as “blades” to fit within the cabinet, with each of the individual enclosures being substantially higher than it is wide, and with electrical connections with the individual systems including an array of contact terminals extending from the rear of each individual enclosure. Each such electronic enclosure is inserted into a slot within the cabinet from the front. Since a large number of electrical connections are made when the enclosure is fully inserted, an insertion/ejection mechanism is configured to provide a mechanical advantage helping to move the enclosure with these terminals to engage contacts within the cabinet, i.e. during an end portion of the process of inserting the enclosure within the slot and during a beginning portion of the process of ejecting the enclosure from the slot.
For example, in the IBM BladeCenter™, each of the electronic enclosures is provided with an upper lever pivotally mounted on its left side near its upper front corner and with a lower lever pivotally mounted on the left side near its lower front corner. The upper lever includes a tooth extending upward within a slot in an upper panel extending above the enclosure when the enclosure is fully inserted within the cabinet. Similarly, the lower lever includes a tooth extending downward within a slot in a lower panel extending below the enclosure when the enclosure is fully inserted within the cabinet. Before the electronic enclosure can be fully inserted within the cabinet, both the upper lever and the lower lever must be pivoted into an open position, with the teeth of the levers extending inward, out of contact with the upper and lower panels, and with handle portions of the levers extending outward. Then the process of inserting the enclosure into the cabinet is completed by pivoting the levers into their closed position, with the teeth of the levers engaging adjacent edges of the slots in the panels to pull the enclosure inward against the forces developed to establish electrical connections by engaging contact springs with multiple terminals. When the electronic enclosure is to be removed from the cabinet, this procedure is reversed, with the upper and lower levers being pivoted into the open position so that the teeth of these levers engage edges of the slots to eject the enclosure outwardly as the various terminals are disconnected from the contact springs.
Within the upper and lower panels, the slots are uniformly spaced apart to provide for filling the cabinet with a number of electronic enclosures, each having a common, minimum width. For each of the electronic enclosures, the upper and lower levers operate, respectively, in a pair of slots that are vertically aligned along the left side of the enclosure. While this arrangement is satisfactory for electronic enclosures having the common, minimum width, it does not work well with larger enclosures having a multiple of the common, minimum width. Since such wider enclosures typically have contact terminal patterns extending across a width greater than the common, minimum width, the use of such an arrangement of levers to install and eject the wider enclosure can result in difficulties caused by twisting the enclosure along guide surfaces of the cabinet and contact surfaces during insertion and injection, with the forces generated by the movement of the lever teeth within the slots in the upper and lower panels. Thus, what is needed is an insertion and ejection mechanism applying forces at two or more locations along the width of a wider enclosure.
Furthermore, the width of an individual electronic enclosure can be increased by adding one or more expansion units, fastened to either side, or both sides, of the enclosure. For example, an expansion unit may include additional hard disk drives to provide increased storage capacity. Therefore, what is additionally needed is a method for adding a mechanism to apply additional insertion and ejection forces when an expansion unit is added to an electronic enclosure.
U.S. Pat. App. Pub. Nos. 2003/0101304 and 2003/0030993 describe a blade server having an ejector mechanism including a pivotable handle. In particular, the '304 publication describes the blade server as being configured as a field replaceable unit removably receivable in a carrier of a modular computer system, such as a high-density blade server system. The blade server is provided with an enclosure and can be provided with a plurality of processors within the enclosure, which may be larger than a standard enclosure for a blade server having a single processor. The carrier can be configured to receive such an oversized blade server enclosure as well as a standard enclosure. The '993 publication particularly describes the ejector mechanism, which can possibly also act as an injection mechanism, as being located at the elongate front face of the blade server and as including an elongate lever extending substantially along the elongate front face. A pivotal mounting for the lever is located toward a first end thereof, and an ejection protrusion is also provided at the first end. In a blade server having a greater width than a conventional blade server, the lever and ejector mechanism are shown as extending across only the portion of the width of the blade server corresponding to the width of a conventional blade server. Thus, the number of contact surfaces for insertion and ejection is not increased when the width of the blade server is increased, and the distance between contact surfaces is likewise not increased. What is needed is an arrangement providing additional contact surfaces for insertion and ejection when the width of an individual blade is increased and for providing an increased distance between such contact surfaces in the direction of increased blade width.
U.S. Pat. No. 5,173,845 describes a frontplane structure for use with a number of parallel printed circuit boards having respective sets of a plurality of electrical connectors mounted to their front edges. The frontplane structure includes a multi-layer printed circuit board mounted to a sheet metal sub-chassis that includes integral injector/ejector devices which, by means of a cam action, produce a reduction in the mechanical effort required to mate the frontplane with each of the connectors contained on the number of printed circuit board assemblies installed into a card cage assembly or computer chassis to which the frontplane is to be connected. A plurality of high-density printed circuit connectors are mounted to the multi-layer printed circuit board for interconnecting with the sets of connectors mounted to the front edge of the printed circuit board assemblies. What is needed is an arrangement providing a number of contact surfaces for the insertion and ejection of individual electronic modules without removing a frontally disposed structure from all of the modules.
U.S. Pat. No. 4,995,821 describes a system for latching a plurality of connector modules or multimodule units in an array to a panel, with the system including opposing parallel assemblies mounted to the panel, each having a plurality of cam levers in associated opposing pairs at each module site. The cam levers are mounted along respective shafts of the assemblies, being adapted to be reciprocally rotatable about the outwardly from and inwardly toward the array. Each cam lever includes a recess into which a latching projection of a module is receivable upon module insertion into the array. When the cam lever is rotated inwardly, the recess urges the module into a fully mated position in its receptacle connector. When the cam lever is rotated outwardly, the recess raises the projection, ejecting the module from the receptacle connector. Several cam levers can be ganged together by means of a pin extending through holes in the cam levers near an end opposite the end at which the cam levers are pivoted, to be rotatable outwardly as a unit, corresponding to several modules ganged as a unit. What is needed is a method for varying the arrangement of cam levers pivotally mounted on individual modules to compensate for dimensional variations among the various modules. Furthermore, while U.S. Pat. Nos. 5,173,845 and 4,995,821 describe methods for ganging cam levers together with shafts or pins extending through an end of the levers opposite the end at which they are pivotally mounted, what is needed is a method for simply extending a pivot shaft arrangement to gang such levers together.
U.S. Pat. No. 5,426,567 describes a structure including similar electronic module packages having guide pins and front actuated retaining rods for mounting the packages on a mounting panel having threaded mounting holes spaced in a regular pattern to accept the guide pins and retaining rods of several module packages. The guide pins and retaining rods are mounted on diagonally opposite corners of the modules. Various arrangements of modules on the mounting panel are allowed by suitable arrangement of the pattern of mounting holes in the panel. While the retaining rods fasten modules of varying size to the panel, forces to engage and disengage connector terminals during the installation and removal of the modules are not provided by the retaining rods.